Pen for three-dimensional printing



FIG. 1 is a front view of the pen for three-dimensional printing,according to an embodiment of the present invention;

FIG. 2 is a bottom view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a left side view thereof; and,

FIG. 7 is a perspective view thereof.

CLAIM The ornamental design for a pen for three-dimensional printing, asshown and described.